Generally, an IC card used as a portable electronic device is provided with a card-like main body formed of plastic or the like, and an IC module embedded in the main body. The IC module has an IC chip and a contact pattern. The IC chip has a nonvolatile memory which can hold data in a state that a power source is not provided, and a CPU to execute various operations. The contact pattern is an interface for electrically connecting a contact terminal which a card reader/writer of a terminal device to process the IC card has, and the IC chip.
In addition, as an IC card, for example, there is a Subscriber Identity Module (SIM) card, or a User Identify Module (UIM) card or the like which is used by being inserted into a terminal device such as a portable telephone. For example, in “ETSI TS 102 221”, shapes such as “Plug-in Universal Integrated Circuit Card (UICC)”, “Mini-UICC”, and “Fourth Form Factor (4FF)” are specified.
A shape of an IC card which can be inserted into a terminal device is determined by the specification of terminal device. For example, in order to insert an IC card with a shape different from the specification of terminal device into a terminal device, there is an adapter (an IC card substrate) for converting the relevant IC card into an IC card with another larger shape.
An IC card substrate as described above has a depression provided for fitting an IC card therein. But, when an IC card substrate is inserted into a terminal device in a state that an IC card is not fitted on the IC card substrate, there is a case in which a contact terminal that a card reader/writer of the terminal device has is caught in the depression of the IC card substrate, and thereby the IC card substrate cannot be taken out from the terminal device.